Nokia has issued a product advisory for the BL-5C battery due to potential short circuit issues while charging. The batteries were manufactured by Matsushita Battery Industrial Co. between December 2005 and November 2006. There are other BL-5C batteries that this advisory does not apply to. In order to see if the battery in your Nokia device is subject to the advisory then you need to pull out the battery and enter the 26 digit identification number into the box on the advisory site. BL-5C batteries can be found in a large number of different Nokia models, including the Nokia N70, N91, E50, 7610, and many others listed on the advisory site.